In recent years, qualities required for lens barrels have been increased and both high performances and high reliability have been required. In terms of optical performances, an adjuster for adjusting the position of a lens and the like is provided in many cases to enhance description performance. A lens barrel capable of adjusting the eccentricity and inclination of an optical element with respect to an optical axis is disclosed, for example, in JP2013-238792A (patent literature 1). An adjusting mechanism disclosed in this patent literature 1 is such that eccentricity adjustment roller mounting portions for adjusting the eccentricity of a fourth length group holding frame and inclination adjustment roller mounting portions for adjusting the inclination of the fourth length group holding frame are both provided at three positions spaced apart in a circumferential direction on the outer periphery of the fourth lens group holding frame (frame body) arranged on a side closest to an image and the eccentricity and inclination are made adjustable by rotating eccentricity adjustment rollers mounted in the eccentricity adjustment roller mounting portions and inclination adjustment rollers mounted in the inclination adjustment roller mounting portions. By fixing a mount member as a mounting member on which a camera main body is to be mounted to a fixing cylinder as a frame body holding member holding the fourth lens group holding frame via an exterior ring by screws after those adjustments, the eccentricity adjustment rollers mounted in the eccentricity adjustment roller mounting portions and the inclination adjustment rollers mounted in the inclination adjustment roller mounting portions are covered over by the mount member and the exterior ring.
However, in the above literature 1, the mount member as the mounting member is fixed to the fixing cylinder after the eccentricity adjustment and the inclination adjustment of the fourth lens group holding frame are made by rotating the eccentricity adjustment rollers and the inclination adjustment rollers. Thus, the position of the fourth lens group holding frame (lens) and the like already adjusted may vary due to a distortion of a member and the like in fixing the mount member, resulting in performance degradation.